Fulcrum connection



Dec. 28 1926.

H. C. SCHAPER FULCRUM CONNECTION Filed April 15, 1923 fizlerziar 6. 2; r

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Patented Dec 28, 1926.

UNlTED STATES PATENT ()FHCE.

HARRY C. SCHAPER, OF ST. LOUIS, MISSOURI ASSIGIIQB T= VJEIGI-ITO--GRAPH GOM- PANY, OF ST. LOUIS, MISSOURI, .A. CORE'GRN ..-i

FULCRUM CONNECT My invention relates generally useful lmprovements 111 fulcrum 1923.- Serial to new and connections Number 507,492.

The objects of the invention are to provide simple and highly eflicient pivot connections for the interengagred load receiving levers whereby friction is reduced to minimum without impairing the load-responsiveness of the levers.

Further objects of the invention are to provide a double-knife edge pivot member for the load actuated levers and means for retaining" said oivot to provide member in operative relation with one of said levers.

With these and other objects in view my ings, in which Fi 'ure l is a lon itudinal cross section through the base of a scale and showing the Weight receivmg platform arranged thereon.

Figure 2 is a fragmental plan load-actuated levers and showin engagement thereof.

view of the the inter- Figure 3 is a vertical cross section taken on line 33 of Figure 2.

Figure 4; is a vertical cross section taken on line 4l4 of Figure 3.

Figure 5 is an end elevation of the pivot member and one of the bearing showing means for retaining: said blocks and pivot memher in operative relation with said block.

Figure 6 1s a perspective detail view of one of the retaining plates.

Referring by numerals to the l ccompanying drawings, 10 indicates box-shaped base which houses the load receiving lever systern of a scale. PIOJGOUIIQ inwardly from the side walls of said base are portions 11 in which are mount cylindrical ed bearings 12. The upper ends of these hearings carry bearing blocks 14 having upwardly presented V-shaped grooves in which are arranged the knife edges of pivot members 15. These pivot members are fixed in the ends of a pair of spaced parallel bars 16 and 17, tran versely disposed in the base 10.

A bar l6 507,492. Divided this application filed April 13, No. 631,901.

which occupies the forward end of the base 10 has inwardl; projecting arms 16" to the extremities of which are fixed upwardly presented knife-edge pivot members 13. The bar 17 which is locatcd toward the rear of the base 10 has inwardlv projecting arms 17 and the extremities theiof are pro led with upwardly presented pivot members similar to the members 18. a

A hearing block 19 carried by the upper end of a loop 20 is pro dried with a ddwnwardly presented V-shaped groove which is designed to be engaged by th knife eds-e of the pivot member 18 and support the loops 20 on the arms 16 and 17? These loops straddle the ends of said arms. and the lower ends of said loops are designed to receive the hooked upper ends o'f short rods 2 The lower ends of said rods have adjustably mounted thereon semi-spherical members which are received in hearings formed in the undersides of the stirrups 2e; and support the same in position. The upper ends of the stirrups 24 are secured to, 01 formed integral with a spider which extends up wardly through a suitable opening formed in the upper end of the base 10. This spider is provided at its corners. and prefei'ahlv in vertical alignment with pivot connections 19. 20, and with bosses 26 having suitable sockets for receiving the pins 27 and platform 28. Thus the platform 9.8 which is ar ranged above the spider and is spaced from and surrounds the upper end of the base 10, is supported in position and suspended from the arms 16 and 17 by the loops 20 and the stirrups 2 1.

A lever 29 is fixed at its forward end to the bar 16 and extends rearwardly in the base 10 and its extreme rear end carries a nose portion 30, which is desi trncd to be enhv a loop 31. fixed to the lower end of steelyard rod 32 the upper end of which is connected to suitable weight indicating mechanism. A lever 34 extends inws and forwardly from bar 17 and is pre ably bifurcated at 34 to clear the it and the forward end of le upwardly through a slot torn lever and is pr w d w h a bar;

7 position i l which is adapted to engage the upwardly presented knife edge of a pivot member 39.

A bearing block 40, having an upwardly presented Vshaped groove 41, is carried by the lever 29 and extends across the slot 35 and receives the downwardly presented edge of the member 39. Thus the member 39 forms a double-knife edge pivot connection between the levers 29 and 34, and this connection is flexible and self-centering and maintains the interengaged levers in their proper operative relation.

The bearing block 37 is preferably held in position by a pin 42 which passes through said blockl and is seated in the horizontal portion 36. This pin is centrally located in said portion and permits slight rocking movement of block 37 whereby the latter can automatically adjust itself with respect to the block and the member 39. In order to prevent displacement of the member 39, during the assembling of the device, said member is preferably retained in operative relation with the bearing block 37 by means of retaining plates 44, which are secured to the block 37 by suitable fastening devices 45 and are provided at their lower ends with inwardly presented lateral projections 46. The member 39 is provided at its ends with" outwardly projecting portions 47 which; when the member 39 is seated in the blocks 37 and 40; are spaced from the projections 46 so that the latter cannot interfere with member 39. However, when the lever 34 or the blocks 37 are moved or disengaged from the lever 29 the projections 46 of the plates 44 will engage the fingers 47 and retain the member 39 in its operative relation with the block 37, thereby preventing displacement or loss of said member.

I claim:

1. An operative connection "for a system of interengaged levers comprising a pair of opposed bearing blocks, and a doubleknife edge member interposed between said blocks and in operative engagement therewith.

2. A. pivot connection for a system of interengaged levers comprising a pair of opposed grooved bearing blocks, and a doubledmit'e edge member interposed between said bloclrs and having bearings therein for transmitting the load from one bearingblock to the other i 3. An operative connection for a system of intcrengaged levers comprising a pair of opposed bearing blocks, a double-knife edge member adapted to be interposed between said blocks and have operative engagement therewith. and means for retaining said. double-knife ed e member in operative relation with one of said bearing blocks.

4. A iulcrum connection for a pair ct load receiving levers comprising a pair of opposed bearing blocks adapted to be arranged in the respective levers, and a double-knife dge member engaging said blocks and operatively interengaging said levers.

5. A fulcrum connection for a pair of load receiving levers comprising a pair of epgosed bearing blocks adapted to be arranged in the respective levers, an d a doublelznite edge member engaging said blocks and operatively interengaging said levers, and means for retaining said double-knife edge member in operative relation with one of said levers.

6. A pivot connection for a system of interengaged levers comprising a pair of opposed grooved bearing blocks, a double knife-edge member having bearings in said blocks. and retaining plates fixed to one of said blocks and having means normally disengaged from said member and adapted to "engage said member and retain it in operative relation with the respective block when the latter occupies a displaced position.

7. In a device of the class described, the combination with a pair of cooperating levers. of a double-knife edge fulcrum member operatively interengaging said levers. and means for retaining said fulcrum member in operative relation with one of said levers.

8. In a device of the class described the combination oi a pair of levers, a V-shape grooved bearing block fixed to one of said levers, another V-shape grooved bearing block adjustably arainged in the other one of said levers in operative relation with the first-mentioned bearing block, and a doublet knife edge member engaging said bearing blocks and forming an interengaging fulcrum connection for said levers.

9. In a weighing scale, the combination with a beam lever, of a lever having a knifeedge hearing at one end and an operative connection with said beam lever at its other end. a lever oppositely disposed to the first mentioned lever and having a knife-edge bearing at its remote end. the other end being aranged above the first lever, and a double knife-edge'member having bearing in said levers at a point equidistant from the tulcrums of said levers.

10. In a weighing scale, the combination with a beam lever, of a lever having a knifeedge pivot atone end, and an operative connection with said beam lever at its other end. a lever oppositely disposed to the first mentioned. lever and having a knife-edge pivot at the remote end. a double knife-edge pivot member having coo erative bearings in said levers, the pivots of said cooperating levers and the operative connection between one of said levers and said beam lever being arranged on the same horizontal plane and said double edge pivot member having its bearing edges arranged equidistant above and below said horizontal plane.

11. In a weighing scale, the combination with a beam lever, of a lever having a knife edge pivot at one end and an operative connection with said beam lever at its other end, alever oppositely disposed to and parallel with the first mentioned lever and having a knife-edge pivot at its remote end, the other end being arranged above the first lever, a double knife-edge pivot member having hearings in said levers at a point 10 equidistant from the pivots of said levers, and means for retaining said double knifeedge pivot member in assembled relation with one of said levers.

In testimony whereof I hereunto afiix my 15 signature this 30th day of March, 1923.

HARRY O. SGHAPER. 

